Keywords
Citation
(1999), "Online particle analyzer for explosive environments", Pigment & Resin Technology, Vol. 28 No. 5. https://doi.org/10.1108/prt.1999.12928ead.006
Publisher
:Emerald Group Publishing Limited
Copyright © 1999, MCB UP Limited
Online particle analyzer for explosive environments
Online particle analyzer for explosive environments
Keywords: Malvern, Hazardous materials, Explosives, Safety
Malvern Instruments reports that it has introduced a new purged flow control option for its EPCS online particle size analyzer that enables safe operation in potentially explosive environments Zone 1 and Zone 2 (hazardous gases).
According to Malvern, when installed with the new option, the EPCS conforms to the requirements of EN 50016:1996 relating to electrical apparatus for potentially explosive atmospheres.
The EPCS operates by sampling directly from a process flowstream, with sample material channelled through a by-pass system running parallel to the main feed. Samples pass through the EPCS laser beam and are returned to the main stream, allowing continuous monitoring of particle size distribution and concentration.
The new purged flow control option works by allowing the maintenance of an overpressure of protective gas flowing through the individual compartments and enclosures of the EPCS. The protective gas used is standard factory grade compressed air. However, for more demanding applications other inert gases such as nitrogen can be used.
When the EPCS is first switched on, a high flow rate purge cycle is initiated, before any power is applied to the system. This is designed to flush out and dilute any gases that may have collected in the EPCS while not in use.
On completion of the purge cycle (typically between 1 and 10 minutes), the gas flow is said to be reduced to operating levels and power is switched on. Throughout operation, flow and pressure are monitored continuously. Any failure causes power to be shut down, necessitating a repeat of the purge cycle before power can be restored to the EPCS.
Further details are available from Malvern Instruments Ltd. Tel: + 44 (0) 1684 892456; Fax: + 44 (0) 1684 892789; E-mail: janr@malvern.co.uk Website: http://www.malvern.co.uk